Snc\RedisBundle\DependencyInjection\Configuration\Configuration::addSwiftMailerSection PHP Method

    private function addSwiftMailerSection(ArrayNodeDefinition $rootNode)
    {
        $rootNode->children()->arrayNode('swiftmailer')->canBeUnset()->children()->scalarNode('client')->isRequired()->end()->scalarNode('key')->isRequired()->end()->end()->end()->end();
    }